Combustion prediction method and combustion prediction system

Abstract

The invention discloses a combustion prediction method and a combustion prediction system. The combustion prediction method comprises the following steps: S1, determining a self-modeling flow field of a combustion chamber; s2, flame response of the fuel in the combustion chamber is determined; s3, constructing a chemical reactor network model; s4, combustion of fuel is simulated, and the NOx concentration of an outlet of a combustion chamber is calculated and recorded; s5, constructing a one-dimensional thermo-acoustic network model according to the structure of the combustion chamber, and performing boundary setting on the one-dimensional thermo-acoustic network model; s6, flame response is introduced into the one-dimensional thermo-acoustic network model, intrinsic calculation is carried out, and the growth rate is recorded; s7, the layout of the fuel is changed, and the steps S2-S6 are repeated until all the set layouts of the fuel are performed; s8, judging whether combustion corresponding to the fuel layout is stable or not according to the growth rate; and S9, the corresponding fuel layout with the minimum NOx concentration in the stable combustion fuel layouts is screened out. According to the combustion prediction method provided by the invention, the combustion result of the fuel layout can be predicted in consideration of the NOx emission concentration and the combustion stability.

Description

Technical Field

[0001] This invention relates to the field of combustion technology, and in particular to a combustion prediction method and a combustion prediction system. Background Technology

[0002] Gas turbine units typically operate at a balance between environmental performance targets and oscillating combustion to ensure equipment and operational safety during low-emission operation. During combustion adjustment in gas turbine units, suitable fuel layouts are selected and adjusted based on combustion predictions of the fuel distribution within the combustion chamber. However, currently, there is a lack of prediction methods that integrate NOx emission predictions with combustion stability predictions. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a combustion prediction method that can predict the combustion stability and NOx emission data of fuel layout, thereby selecting a fuel layout that takes into account both combustion stability and NOx emission.

[0004] The present invention also proposes a combustion prediction system that applies the above-mentioned combustion prediction method.

[0005] According to a combustion prediction method of the first aspect of the present invention, the method includes: S1, determining the self-modeled flow field of the combustion chamber; S2, determining the flame response of the fuel in the combustion chamber; S3, constructing a chemical reactor network model; S4, simulating the combustion of the fuel using the chemical reactor network model, calculating and recording the NOx concentration at the combustion chamber outlet; S6, importing the flame response into a one-dimensional thermoacoustic network model, intrinsically calculating and recording the growth rate; S7, changing the fuel layout, repeating steps S2-S6 until all the set fuel layouts have undergone steps S2-S6; S8, determining whether the combustion corresponding to the fuel layout is stable based on the growth rate; S9, selecting the fuel layout with the lowest NOx concentration among the stable combustion fuel layouts.

[0006] According to the combustion prediction method of the first aspect of the present invention, NOx concentration emission data is predicted by a chemical reactor network model and combustion stability is predicted by a one-dimensional thermoacoustic network model. The combustion stability and NOx concentration emission data of the fuel layout can be predicted, thereby selecting a fuel layout that takes into account both combustion stability and NOx concentration emission, and the prediction speed is relatively fast.

[0007] According to some embodiments of the present invention, in step S1, the self-modeled flow field of the combustion chamber is determined by CFD calculation.

[0008] According to some embodiments of the present invention, in step S3, the chemical reactor network model includes: a fully stirred reactor (PSR) for simulating a homogeneous combustion zone; a plug flow reactor (PFR) for simulating a directional flow reaction zone; and a mixer (MIX) for simulating the mixing of gases without chemical reaction.

[0009] According to some embodiments of the present invention, in step S2, the flame response of the fuel in the combustion chamber is determined by CFD calculation.

[0010] According to some embodiments of the present invention, in step S6, the growth rate is determined by solving the thermoacoustic system matrix equation. Calculate, where the eigenvalue λ = σ + jw, A is the system matrix, and I is the identity matrix. Let σ (real part) be the eigenvector, and let σ (real part) be the growth rate (unit: s). -1 ), where j is the imaginary unit and ω (imaginary part) is the angular frequency.

[0011] According to some embodiments of the present invention, in step S8, if the absolute value of the growth rate is greater than or equal to 1s -1 If the combustion is stable, then the combustion is determined to be stable.

[0012] According to some embodiments of the present invention, the fuel layout includes: the proportion of each component of the fuel, the fuel equivalence ratio, and the fuel distribution.

[0013] According to some embodiments of the present invention, the parameters for the boundary settings include: inlet boundary: pressure, temperature, velocity, reflection amplitude, and delay; heat source surface: fuel type, equivalence ratio, and heat release rate; outlet boundary: reflection amplitude and delay.

[0014] According to some embodiments of the present invention, the one-dimensional thermoacoustic network model simplifies the combustion chamber into a longitudinal chain of acoustic elements.

[0015] According to the combustion prediction system of the second aspect of the present invention, the combustion prediction method of the first aspect of the present invention is applied.

[0016] According to the combustion prediction system of the second aspect of the present invention, by applying the combustion prediction method of the first aspect of the present invention, the combustion stability and NOx concentration emission data of the fuel layout can be predicted, thereby selecting a fuel layout that takes into account both combustion stability and NOx concentration emission, and the prediction speed is relatively fast during the prediction process.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] Figure 1This is a flowchart of a combustion prediction method according to an embodiment of the present invention;

[0019] Figure 2 This is a flow field cloud map of the combustion chamber in the combustion prediction method according to an embodiment of the present invention. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] The following is for reference. Figure 1 A combustion prediction method according to an embodiment of the first aspect of the present invention is described.

[0022] like Figure 1 As shown, the combustion prediction method according to a first aspect embodiment of the present invention includes:

[0023] S1. Determine the self-modeled flow field of the combustion chamber.

[0024] The combustion chamber structure is modeled in CFD software, and then the self-modeled flow field of the combustion chamber is obtained through CFD calculation. The self-modeled flow field means that the flow field satisfies similarity transformation in space or time, and the flow field morphology remains unchanged when the geometric scale or operating conditions change.

[0025] S2. Determine the flame response of the fuel in the combustion chamber.

[0026] Flame response refers to the response characteristics of a flame to external disturbances (such as changes in flow rate, pressure, temperature, equivalence ratio, etc.), including its structure, location, stability, or dynamic behavior. Flame response is quantified using the flame transfer function (FTF) and / or the flame description function (FDF).

[0027] S3. Construct a chemical reactor network model.

[0028] Among them, the chemical reactor network is divided according to the self-modeling flow field and the temperature distribution of the combustion chamber.

[0029] S4. Simulate fuel combustion using a chemical reactor network model, calculate and record the NOx concentration at the combustion chamber outlet.

[0030] The chemical reactor network includes: a fully stirred reactor (PSR) to simulate a homogeneous combustion zone, a plug flow reactor (PFR) to simulate a directional flow reaction zone, and a mixer (MIX) to simulate the mixing of gases without chemical reaction.

[0031] S5. Construct a one-dimensional thermoacoustic network model based on the structure of the combustion chamber, and set the boundaries of the one-dimensional thermoacoustic network model.

[0032] The one-dimensional thermoacoustic network model only considers the longitudinal propagation of disturbances. Boundary settings are applied to the one-dimensional thermoacoustic network model based on boundary conditions, fuel conditions, and flame response. The parameters for these boundary settings include:

[0033] Inlet boundary: pressure, temperature, velocity, reflection amplitude, delay;

[0034] Heat source: fuel type, equivalence ratio, heat release rate;

[0035] Export boundary: reflection amplitude, delay.

[0036] S6. Import the flame response into the one-dimensional thermoacoustic network model, calculate the intrinsic growth rate, and record the growth rate.

[0037] The growth rate reflects the trend of characteristic frequency changes, that is, the growth rate reflects the degree of combustion stability. The smaller the absolute value of the growth rate, the higher the degree of combustion stability; the larger the absolute value of the growth rate, the worse the degree of combustion stability.

[0038] S7. Change the fuel layout and repeat steps S2-S6 until all fuel layout settings have been performed using steps S2-S6.

[0039] The fuel layout includes the proportion of each fuel component, the fuel equivalence ratio, and the fuel distribution. That is, the fuel layout is used as the independent variable, and NOx concentration and combustion stability are used as the dependent variables.

[0040] By sequentially using different fuel layouts as independent variables, the predicted NOx concentration at the combustion chamber outlet is obtained through a chemical reactor network model, and the predicted combustion stability is obtained through intrinsic calculations using a one-dimensional thermoacoustic network.

[0041] S8. Determine whether the combustion corresponding to the fuel layout is stable based on the growth rate.

[0042] The stability of combustion corresponding to the fuel layout is determined by comparing the absolute value of the growth rate with a set value. For example, the set value can be set to 1. If the absolute value of the growth rate is greater than or equal to 1 second... -1 If the combustion is stable, the fuel layout is considered stable; otherwise, the fuel layout is considered unstable.

[0043] S9. Select the fuel layout with the lowest NOx concentration among the stable combustion fuel layouts.

[0044] After selecting fuel layouts that meet the requirements for combustion stability, the predicted NOx concentration data corresponding to the above fuel layouts are compared. The fuel layout with the lowest NOx concentration is the optimal fuel layout that balances combustion stability and NOx emission in the predicted set fuel layout operating conditions.

[0045] The combustion prediction system used to implement the combustion prediction method can be integrated into the combustion control system of the gas turbine unit. The combustion control system adjusts the fuel layout of the gas turbine unit according to the prediction results of the combustion prediction system. Alternatively, the combustion prediction system can work independently, and the operator can manually adjust the fuel layout of the gas turbine unit through the combustion control system of the gas turbine unit according to the prediction results of the combustion prediction system.

[0046] According to the combustion prediction method of the first aspect of the present invention, NOx concentration emission data is predicted by a chemical reactor network model and combustion stability is predicted by a one-dimensional thermoacoustic network model. The combustion stability and NOx concentration emission data of the fuel layout can be predicted, thereby selecting a fuel layout that takes into account both combustion stability and NOx concentration emission, and the prediction speed is relatively fast.

[0047] In some embodiments of the present invention, in step S1, the self-modeled flow field of the combustion chamber is determined by CFD calculation.

[0048] In the CFD calculation process, CFD modeling is first performed based on the actual structure of the combustion chamber. Then, CFD calculations are conducted on the combustion chamber model to obtain the self-modeled flow field of the combustion chamber. CFD calculations yield high-precision data, and they can integrate relatively complex physical models. Determining the self-modeled flow field of the combustion chamber through CFD calculations can improve the accuracy of prediction data.

[0049] In some embodiments of the present invention, in step S3, the chemical reactor network model includes: a fully stirred reactor (PSR), a plug flow reactor (PFR), and a mixer (MIX).

[0050] Specifically, a fully stirred reactor (PSR) is used to simulate a homogeneous combustion zone. A PSR is an ideal zero-dimensional model. When the flow rate is constant, the reactants quickly and uniformly distribute throughout the reactor space and mix thoroughly with the products. Therefore, the chemical reaction rate is the primary factor determining the product conversion rate.

[0051] The basic properties of the PSR model are shown in the table below. The inlet flow rate of the fully stirred reactor (PSR) is given by the inlet boundary conditions or by the outlet parameters of the previous reactor. Parameters such as flow rate, temperature, pressure, and composition can be defined in the inlet boundary conditions. When the inlet flow rate is given, the other parameter in a fully stirred reactor (PSR) can be determined by giving either the reactor volume or the residence time.

[0052] symbol name unit Physical meaning V reactor volume <![CDATA[m 3 ]]> PSR reactor volume <![CDATA[τ r ]]> Duration of stay s Chemical reaction time T initial temperature K Reactor initial temperature p pressure Pa reactor pressure

[0053] A fully stirred reactor (PSR) involves energy and concentration conservation equations.

[0054] The PSR concentration conservation equation is:

[0055]

[0056] Where Y k W is the mass fraction of the k-th component (there are K components in total); k It is the molecular weight of the k-th component; ρ is the molar rate per unit volume of the k-th component; ρ is the density of the mixture; the superscript * indicates the outlet state.

[0057] The PSR energy conservation equation is:

[0058]

[0059] In the formula C p h is the average specific heat. k Let be the specific enthalpy of the k-th component; Q be the heat loss of the reactor.

[0060] A plug flow reactor (PFR) is used to simulate a directional flow reaction zone. The PFR is a one-dimensional ideal model, its volume characterized by the cross-sectional area and length of the pipe. This model assumes that reactants flow only along the axial direction within the pipe, that the composition and reaction rate remain constant regardless of radial position or reaction time, that reactants are uniformly mixed only radially and not axially, and that the chemical reaction time within the reactor is much shorter than the chemical mixing time.

[0061] The basic properties of the PFR model are shown in the table below. The inlet flow rate and composition of the plug flow reactor (PFR) are given by the inlet boundary conditions or are the outlet parameters of the previous reactor. Parameters such as flow rate, temperature, pressure, and composition can be defined in the inlet boundary conditions.

[0062] symbol name unit Physical meaning A Cross-sectional area <![CDATA[m 2 ]]> PFR reactor cross-sectional area L length m PFR reactor length T temperature K Reactor initial temperature P pressure Pa reactor pressure

[0063] The governing equations of a plug flow reactor (PFR) include the mass conservation equation, energy conservation equation, concentration conservation equation, and momentum conservation equation.

[0064] The mass conservation equation for PFR is:

[0065]

[0066] Where u represents k g The axial velocity of the gas composed of the three components, W k S represents the molecular weight of component K. k Represents the molar productivity of component K through all surface reactions, where A is the cross-sectional area of ​​the fluid flow, and a i,m The effective internal surface area per unit length of a substance is represented by m.

[0067] The PFR concentration conservation equation is:

[0068]

[0069] Where Y k It is the mass fraction of component k. It is the formation rate of component k in the gas phase reaction.

[0070] The energy conservation equation for PFR is:

[0071]

[0072] Where h k It is the enthalpy of component k. T is the average heat capacity of the gas, and T is the temperature of the gas. It is the molar formation rate of component k that reacts with substance m on the surface.

[0073] The momentum conservation equation for PFR is:

[0074]

[0075] Where P is the absolute pressure and F is the resistance applied to the gas.

[0076] The Mixer (MIX) is used to simulate the mixing of gases without chemical reactions. An ideal mixer (MIX) simulates the uniform mixing of multiple gases within the mixer without any chemical reactions. The basic properties of the MIX model are shown in the table below.

[0077]

[0078] The mixer (MIX) follows the mass conservation equation, the component conservation equation, and the energy conservation equation.

[0079] The mass conservation equation for MIX is:

[0080]

[0081] The MIX component conservation equation is:

[0082]

[0083] The MIX energy conservation equation is:

[0084]

[0085] In some embodiments of the present invention, in step S2, the flame response of the fuel in the combustion chamber is determined by CFD calculation.

[0086] CFD calculations yield high-precision data and can integrate complex physical models. By determining the flame response of fuel in the combustion chamber through CFD calculations, the accuracy of prediction data can be improved.

[0087] In some embodiments of the present invention, in step S6, the growth rate is determined by solving the thermoacoustic system matrix equation. Calculate, where the eigenvalue λ = σ + jw, A is the system matrix, and I is the identity matrix. Let σ (real part) be the eigenvector, and let σ (real part) be the growth rate (unit: s). -1 ), where j is the imaginary unit and ω (imaginary part) is the angular frequency.

[0088] Solve the matrix equations of the thermoacoustic system Combustion stability can be determined. The system matrix A is constructed from acoustic units, transfer functions, flame response, and damping terms.

[0089] In some embodiments of the present invention, in step S8, if the absolute value of the growth rate is greater than or equal to 1s -1 If the combustion is stable, then the combustion is determined to be stable.

[0090] The growth rate reflects the trend of characteristic frequency changes, that is, the growth rate reflects the degree of combustion stability. The smaller the absolute value of the growth rate, the higher the degree of combustion stability; the larger the absolute value of the growth rate, the worse the degree of combustion stability.

[0091] In some embodiments of the present invention, the fuel layout includes: the proportion of each component of the fuel, the fuel equivalence ratio, and the fuel distribution.

[0092] In the actual prediction process, the proportions of each component of the fuel, the fuel equivalence ratio, and one or more parameters in the fuel distribution can be changed to form a variety of fuel layouts.

[0093] In some embodiments of the present invention, the parameters for boundary setting include:

[0094] Inlet boundary: pressure, temperature, velocity, reflection amplitude, delay;

[0095] Heat source: fuel type, equivalence ratio, heat release rate;

[0096] Export boundary: reflection amplitude, delay.

[0097] In the actual prediction process, the above parameters are adaptively adjusted when predicting each set fuel layout.

[0098] In some embodiments of the present invention, the one-dimensional thermoacoustic network model simplifies the combustion chamber as a longitudinal chain of acoustic elements.

[0099] The volume of each element is determined by the equivalent diameter and length of each part of the combustion chamber, and the volume V of each element satisfies:

[0100] V = π / 4 * Deq 2 *L, where Deq is the equivalent diameter and L is the length.

[0101] The following is for reference. Figure 1 and Figure 2 A specific embodiment of the combustion prediction method according to the present invention is described.

[0102] The combustion chamber includes an intake section, a methane-air premixed swirl channel, a central hydrogen channel, and a cylindrical combustion chamber. The fuel is a mixture of methane and hydrogen.

[0103] S1. The self-modeled flow field of the combustion chamber was determined by CFD calculation, and the flow field contour plot is shown below. Figure 2 As shown.

[0104] S2. The flame response of the fuel in the combustion chamber is obtained by CFD calculation for the initial operating condition. The equivalence ratio of methane to air is 0.8, and the proportion of hydrogen combustion to the total combustion power is 2%. The initial operating condition corresponding to this fuel layout is set as PH2, and the fuel entering the combustion chamber is 18m / s. The flame response includes the temperature distribution in the combustion chamber. The flame response is obtained by flame description function (FDF).

[0105] S3. Construct a chemical reactor network model.

[0106] Based on the self-modeled flow field obtained in step S1 and the temperature inside the combustion chamber obtained in step S2, the combustion chamber in the chemical reactor network is divided into three PSRs and one MIX. The upper and lower PSRs are for methane-air premixed combustion, and the middle PSR is for methane-hydrogen-air mixed combustion. Then, the outlets of the three PSRs are fed into the MIX for mixing.

[0107] S4. The combustion of fuel was simulated using a chemical reactor network model. The NOx concentration at the combustion chamber outlet was calculated and recorded. The calculated NOx concentration at the outlet under this operating condition was 16.8 ppm. Actual combustion under this condition showed that the predicted result deviated little from the actual result.

[0108] S5. Construct a one-dimensional thermoacoustic network model based on the structure of the combustion chamber, and set the boundaries of the one-dimensional thermoacoustic network model.

[0109] The combustion chamber is divided into a rectifying section, a contraction section, a transition section, and a combustion section. The boundary setting parameters are shown in the table below.

[0110]

[0111] S6. Import the flame description function (FDF) obtained in step S2 into the one-dimensional thermoacoustic network model, and intrinsically calculate and record the growth rate.

[0112] S7. Change the fuel layout by changing the hydrogen doping ratio to 0%, 1%, 3%, 4%, and 5% respectively, while keeping the fuel equivalence ratio and injection velocity unchanged. The corresponding operating conditions are (REF, PH1, PH3, PH4, and PH5). Repeat steps S2-S6 until all fuel layout settings have been implemented using steps S2-S6. The specific results are shown in the table below.

[0113] S8. Determine whether the combustion corresponding to the fuel layout is stable based on the relationship between the absolute value of the growth rate and 1. If the absolute value of the growth rate is less than 1, the combustion is determined to be stable. The specific results are shown in the table below.

[0114] Hydrogen doping ratio NOx concentration Combustion stability REF 12.3ppm Unstable PH1 14.5ppm Unstable PH2 16.8ppm Unstable PH3 19.5ppm Unstable PH4 22.4ppm Stablize PH5 25.5ppm Stablize

[0115] S9. Select the fuel layout with the lowest NOx concentration among the stable combustion fuel layouts.

[0116] As shown in the table above, the optimal fuel layout is achieved when the hydrogen blending ratio is 4%.

[0117] The combustion prediction system according to a second aspect of the present invention applies the combustion prediction method according to the first aspect of the present invention.

[0118] The combustion prediction system can be integrated into the combustion control system of the gas turbine unit. The combustion control system adjusts the fuel layout of the gas turbine unit based on the prediction results of the combustion prediction system. Alternatively, the combustion prediction system can work independently, allowing the operator to manually adjust the fuel layout of the gas turbine unit through the combustion control system based on the prediction results of the combustion prediction system.

[0119] According to the combustion prediction system of the second aspect of the present invention, by applying the combustion prediction method of the first aspect of the present invention, the combustion stability and NOx concentration emission data of the fuel layout can be predicted, thereby selecting a fuel layout that takes into account both combustion stability and NOx concentration emission, and the prediction speed is relatively fast.

[0120] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0121] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0122] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0123] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0124] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A combustion prediction method, characterized in that, include: S1. Determine the self-modeled flow field of the combustion chamber; S2. Determine the flame response of the fuel in the combustion chamber; S3. Construct a chemical reactor network model; S4. Simulate fuel combustion using a chemical reactor network model, calculate and record the NOx concentration at the combustion chamber outlet; S5. Construct a one-dimensional thermoacoustic network model based on the structure of the combustion chamber, and set the boundaries of the one-dimensional thermoacoustic network model; S6. Import the flame response into the one-dimensional thermoacoustic network model, calculate the intrinsic growth rate, and record the growth rate. S7. Change the fuel layout and repeat steps S2-S6 until all fuel layout settings have been performed using steps S2-S6. S8. Determine whether the combustion corresponding to the fuel layout is stable based on the growth rate. S9. Select the fuel layout with the lowest NOx concentration among the stable combustion fuel layouts.

2. The combustion prediction method according to claim 1, characterized in that, In step S1, the self-modeled flow field of the combustion chamber is determined by CFD calculation.

3. The combustion prediction method according to claim 1, characterized in that, In step S3, the chemical reactor network model includes: A fully stirred reactor (PSR) is used to simulate a homogeneous combustion zone; Plunger flow reactor (PFR) is used to simulate directional flow reaction zones; A mixer (MIX) is used to simulate the mixing of gases without chemical reaction.

4. The combustion prediction method according to claim 1, characterized in that, In step S2, the flame response of the fuel in the combustion chamber is determined by CFD calculation.

5. The combustion prediction method according to claim 1, characterized in that, In step S6, the growth rate is determined by solving the thermoacoustic system matrix equations. Calculate, where the eigenvalue λ = σ + jw, A is the system matrix, and I is the identity matrix. Let σ (real part) be the eigenvector, and let σ (real part) be the growth rate (unit: s). -1 ), where j is the imaginary unit and ω (imaginary part) is the angular frequency.

6. The combustion prediction method according to claim 1, characterized in that, In step S8, if the absolute value of the growth rate is greater than or equal to 1s -1 If the combustion is stable, then the combustion is determined to be stable.

7. The combustion prediction method according to claim 1, characterized in that, The fuel layout includes: the proportion of each fuel component, the fuel equivalence ratio, and the fuel distribution.

8. The combustion prediction method according to claim 1, characterized in that, The parameters for setting the boundary include: Inlet boundary: pressure, temperature, velocity, reflection amplitude, delay; Heat source: fuel type, equivalence ratio, heat release rate; Export boundary: reflection amplitude, delay.

9. The combustion prediction method according to claim 1, characterized in that, The one-dimensional thermoacoustic network model simplifies the combustion chamber into a longitudinal chain of acoustic elements.

10. A combustion prediction system, characterized in that, The combustion prediction method according to any one of claims 1-9 is applied.

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